what wanque says holds true, i forgot the nes emulator for PC but its going for 100% accuracy as opposed to 100% speed/compatiblity and all that so if there is a slowdown in the real cart on the real system it'll slowdown in that emulator att he same point, super mario 3 has a weird line on it that most emulators get rid of through hacks, but the 100% accuracy emulators still show it. its odd but its true, chances are nintendo is going the accuracy route as opposed to speed/look/allthathappyhorsecrap emulators do on PCs ;P